Detailed characterisation of circulatory nitric oxide and free radical indices—is there evidence for abnormal cardiovascular homeostasis in young women with polycystic ovary syndrome?. (12th May 2014)

• Record Type: Journal Article
• Authors: Willis, GR; Udiawar, M; Evans, WD; Blundell, HL; James, PE; Rees, DA
• Is Part Of: BJOG. Volume 121:Number 13(2014)
• Page Start: 1596
• Page End: 1603
• Publication Date: 2014-05-12
• Subjects: Obstetrics -- Periodicals; Gynecology -- Periodicals; 618
• DOI: 10.1111/1471-0528.12834
• Languages: English
• ISSNs: 1470-0328

Abstract

<abstract abstract-type="main" id="bjo12834-abs-0001"> <title> <x xml:space="preserve">Abstract</x> </title> <sec id="bjo12834-sec-0001" sec-type="section"> <title>Objective</title> <p>To assess circulating biochemical indices of endothelial function and nitro‐oxidative stress in women with polycystic ovary syndrome (PCOS).</p> </sec> <sec id="bjo12834-sec-0002" sec-type="section"> <title>Design</title> <p>Case–control study.</p> </sec> <sec id="bjo12834-sec-0003" sec-type="section"> <title>Population</title> <p>Seventeen women with PCOS and eighteen age‐ and body mass index‐matched healthy volunteers.</p> </sec> <sec id="bjo12834-sec-0004" sec-type="section"> <title>Methods</title> <p>Nitric oxide (NO) metabolite levels were assessed by chemiluminescence. Electron paramagnetic resonance spectroscopy with spin trapping was used to assess oxidative stress <italic>ex vivo</italic> and <italic>in vitro</italic>. Antioxidant capacity was measured using oxygen radical absorbance.</p> </sec> <sec id="bjo12834-sec-0005" sec-type="section"> <title>Main outcome measures</title> <p>Biochemical indices of endothelial function, including NO metabolites, lipid‐derived radicals and antioxidant capacity.</p> </sec> <sec id="bjo12834-sec-0006" sec-type="section"> <title>Results</title> <p>Plasma NO metabolites were similar in the two groups (nitrite: 257 ± 116 nmol/l [PCOS], 261 ± 135 nmol/l [controls] <italic>P </italic>= 0.93; nitrate: 27 ± 7 <italic>μ</italic>mol/l [PCOS], 26 ± 6 <italic>μ</italic>mol/l [controls] <italic>P </italic>= 0.89). Alkoxyl free radicals (lipid‐derived) were detected as the dominant species, but levels were not different between women with PCOS and controls whether measured directly <italic>ex vivo</italic> (median 7.2 [range 0.17–16.73]<sup>e6</sup> arbitrary units [a.u.] and 7.2 [1.7–11.9]<sup>e6</sup> a.u., respectively, <italic>P </italic>= 0.57) or when stimulated <italic>in vitro</italic> to test radical generation capacity (1.23 [0.3–5.62]<sup>e7</sup> a.u. and 1.1 [0.48–15.7]<sup>e7</sup> a.u. respectively, <italic>P </italic>= 0.71). In regression analysis, visceral fat area was independently associated with <italic>in vitro</italic> oxidative potential (<italic>β</italic> = 0.6, <italic>P </italic>= 0.002). Total plasma antioxidant capacity (94 ± 30% [PCOS], 79 ± 24% [controls], <italic>P </italic>= 0.09) and plasma hydroperoxides (7.5 ± 4 <italic>μ</italic>mol/l [PCOS], 6.7 ± 5 <italic>μ</italic>mol/l [controls], <italic>P </italic>= 0.21) were not different between groups. However, lipophilic antioxidant capacity was lower in women with PCOS compared with controls (92 ± 32 and 125 ± 48%, respectively, <italic>P </italic>= 0.02).</p> </sec> <sec id="bjo12834-sec-0007" sec-type="section"> <title>Conclusions</title> <p>Young overweight women with PCOS display a reduced lipophilic antioxidant capacity compared with healthy volunteers, but no change in circulating free radicals or nitro‐oxidative stress.</p> </sec> </abstract>